BRAKING DEVICE

A brake device (40) for braking rotation of an input shaft (46) is provided. The brake device comprises: a selectively operable trigger brake (42) comprising: a static element; a trigger brake shaft (56) mounted for rotational and axial movement relative to the static element and the input shaft (46); a preloaded torsion spring (120) rotationally coupled to the input shaft (46) but permitting a limited rotational movement between the trigger brake shaft (56) and the input shaft (46); a roller jamming mechanism (44) operable upon the relative rotation between the trigger brake shaft (56) and the input shaft (46) exceeding a predetermined amount to stop rotation of the input shaft (46) upon operation of the trigger brake (42); and a brake actuator (62) for selectively moving the trigger brake shaft (56) into and out of engagement with a contact surface of the static element; wherein the engagement of the contact surface of the static element and the trigger brake shaft (56) overcomes the preload of the torsion spring (120) so as to produce a relative rotation between the trigger brake shaft (56) and the input shaft (46) to operate the roller jamming mechanism (44).